1. Field of the invention
The present invention relates to a two-dimensional code extraction method for automatically extracting two-dimensional code images from an image data read into an apparatus such as a computer, using a scanner or other image input device, from sheets upon which the two-dimensional code has been printed on documents or tables.
2. Description of the Related Art
In recent years, the development of two-dimensional code, which can hold more information than conventional bar codes, has progressed and begun to be used in practical applications. The use of two-dimensional code makes it possible to print all manner of binary data, including documents, imaging and audio data, on paper surfaces.
Documents imprinted with two-dimensional code can be transmitted via facsimile or distributed as printed matter. The receiving party can then read in the two-dimensional code as image data by using an image scanner, and restore data to its original state by using software and hardware designed for restoring two-dimensional code.
Among two-dimensional codes are those that can be read using a general type of image scanner. This allows the data to be restored by reading it into a nearby scanner without using a specialized device, giving it the advantage of being read by a wide range of reading devices.
However, if a two-dimensional code is printed on paper not by itself, but alongside documents (text etc.) and diagrams in the desired size and position, it is highly likely that a portion of the accompanying text, diagram or image data, will be scanned along with the two-dimensional code.
When images other than the two-dimensional codes are included in the scanned data, the software or hardware intended to restore the data to its original state cannot restore the scanned data properly, as the software or hardware can not extract a two-dimensional code portion from the others. Therefore, the two-dimensional code portion has to be extracted separately from the other image data that is scanned in.